The RLSWAIT exit is entered at the start of the record management request and the request is processed asynchronously under a separate VSAM execution unit. If a UPAD is specified, RLS ignores it.

The exit can do its own wait processing associated with the record management request that is being asynchronously executed. When the record management request is complete, VSAM will post the ECB that the user specified in the RPL.

For RLS, the RLSWAIT exit is entered only for a request wait, never for a resource- or I/O- wait or post as with non-RLS VSAM UPAD.

The RLSWAIT exit is optional. It is used by applications that cannot tolerate VSAM suspending the execution unit that issued the original record management request. The RLSWAIT exit is required for record management request issued in cross memory mode.

RLSWAIT should be specified on each ACB which requires the exit. If the exit is not specified on the ACB via the EXLST, there is no RLSWAIT exit processing for record management requests associated with that ACB. This differs from non-RLS VSAM where the UPAD exit is associated with the control block structure so that all ACBs connected to that structure inherit the exit of the first connector.

To activate RLSWAIT exit processing for a particular record management request, the RPL must specify OPTCD=(SYN,WAITX). RLSWAIT is ignored if the request is asynchronous.